package com.atguigu.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.to.es.SkuEsModel;
import com.atguigu.common.utils.R;
import com.atguigu.gulimall.search.bo.BrandBo;
import com.atguigu.gulimall.search.config.GulimallElasticSearchConfig;
import com.atguigu.gulimall.search.constant.ESConstant;
import com.atguigu.gulimall.search.feign.ProductFeignService;
import com.atguigu.gulimall.search.service.MallSearchService;
import com.atguigu.gulimall.search.vo.AttrResponseVo;
import com.atguigu.gulimall.search.vo.SearchParam;
import com.atguigu.gulimall.search.vo.SearchResult;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.NestedQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author 孤风雪影
 * @date 2021/1/8
 */
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    private RestHighLevelClient restHighLevelClient;

    @Autowired
    private ProductFeignService productFeignService;

    /**
     * 核心检索方法
     * @param param 检索的所有参数
     * @return
     */
    @Override
    public SearchResult search(SearchParam param) {
        SearchResult result = null;

        //1.准备检索请求
        SearchRequest searchRequest = this.buildSearchRequest(param);

        try {
            //2.执行检索请求
            SearchResponse searchResponse = restHighLevelClient.search(searchRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);
            //3.分析响应数据,封装成需要的格式
            result = this.buildSearchResult(searchResponse, param);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return result;
    }

    /**
     * 准备检索请求
     * @param param
     * @return
     */
    private SearchRequest buildSearchRequest(SearchParam param) {
        //搜索顶层对象Query
        String[] indices = {ESConstant.PRODUCT_INDEX};
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();

        //------------构建DSL语句-------------

        //1. 构建BoolQuery
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();

        //1.1 must-模糊查询
        if (!StringUtils.isEmpty(param.getKeyword())) {
            boolQuery.must(QueryBuilders.matchQuery("skuTitle", param.getKeyword()));
        }

        //1.2 filter-不参与评分
        //1.2.1 bool-filter - 按照三级分类id查询
        if (param.getCatalog3Id() != null) {
            boolQuery.filter(QueryBuilders.termQuery("catalogId", param.getCatalog3Id()));
        }
        //1.2.2 bool-filter - 品牌id查询
        if (!CollectionUtils.isEmpty(param.getBrandId())) {
            boolQuery.filter(QueryBuilders.termsQuery("brandId", param.getBrandId()));
        }
        //1.2.3 bool-filter - 属性查询
        if (!CollectionUtils.isEmpty(param.getAttrs())) {
            for (String attrStr : param.getAttrs()) {
                //attrs=1_5寸:8寸&attrs=2_8G:16G
                BoolQueryBuilder nestedBoolQueryBuilder = QueryBuilders.boolQuery();
                //attrStr=1_5寸:8寸
                String[] s = attrStr.split("_");
                String attrId = s[0];
                String[] attrValues = s[1].split(":");
                nestedBoolQueryBuilder.must(QueryBuilders.termQuery("attrs.attrId", attrId));
                nestedBoolQueryBuilder.must(QueryBuilders.termsQuery("attrs.attrValue", attrValues));
                //每一个attrs，都要生成一个nested查询
                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs", nestedBoolQueryBuilder, ScoreMode.None);
                boolQuery.filter(nestedQuery);
            }

        }

        //1.2.4 bool-filter - 是否拥有库存
        if (param.getHasStock() != null) {
            boolQuery.filter(QueryBuilders.termQuery("hasStock", param.getHasStock() == 1));
        }

        //1.2.5 bool-filter - 价格区间
        if (!StringUtils.isEmpty(param.getSkuPrice())) {
            //1_500 / _500 / 500_
            RangeQueryBuilder skuPriceRange = QueryBuilders.rangeQuery("skuPrice");

            String[] split = param.getSkuPrice().split("_");
            if (split.length == 2) {
                //区间Bug,如果是_600,也会被拆分为2个, "", "6000"
                if ("".equals(split[0])) {
                    skuPriceRange.lte(split[1]);
                } else {
                    //真正的区间判断
                    skuPriceRange.gte(split[0]).lte(split[1]);
                }
            } else if (split.length == 1) {
                // 由于Bug的原因,下面的判断必然成立
                if (param.getSkuPrice().endsWith("_")) {
                    skuPriceRange.gte(split[0]);
                }
            }

            boolQuery.filter(skuPriceRange);
        }

        //把所有的Query条件封装
        searchSourceBuilder.query(boolQuery);

        /**
         * 排序:Sort
         */
        //2. 排序
        if (!StringUtils.isEmpty(param.getSort())) {
            String sort = param.getSort();
            //sort=hotScore_asc/desc
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc") ? SortOrder.ASC : SortOrder.DESC;
            searchSourceBuilder.sort(s[0], order);
        }

        /**
         * 分页:page
         */
        //3. 分页
        searchSourceBuilder.from((param.getPageNum() - 1) * ESConstant.PRODUCT_PAGESIZE);
        searchSourceBuilder.size(ESConstant.PRODUCT_PAGESIZE);

        /**
         * 高亮
         */
        //4.高亮
        if (!StringUtils.isEmpty(param.getKeyword())) {
            HighlightBuilder highlightBuilder = new HighlightBuilder();

            highlightBuilder.field("skuTitle");
            highlightBuilder.preTags("<b style='color:red'>");
            highlightBuilder.postTags("</b>");

            searchSourceBuilder.highlighter(highlightBuilder);
        }

        /**
         * 聚合分析
         */
        //1.品牌聚合
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg").field("brandId").size(50);
        //1.1 品牌聚合的子聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1));
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        searchSourceBuilder.aggregation(brand_agg);

        //2.分类聚合 catalog_agg
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg").field("catalogId").size(20);
        //2.1 分类的子聚合
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        searchSourceBuilder.aggregation(catalog_agg);

        //3.属性聚合
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        //聚合出当前所有的attrId
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        //聚合分析出当前attr_id对应的名字
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        //聚合分析出当前attr_id对应的可能属性值
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
        attr_agg.subAggregation(attr_id_agg);
        searchSourceBuilder.aggregation(attr_agg);


        System.out.println("构建的DSL" + searchSourceBuilder);

        SearchRequest searchRequest = new SearchRequest(indices, searchSourceBuilder);
        return searchRequest;
    }


    /**
     * 构建结果数据
     *
     * @param response
     * @param param
     * @return
     */
    private SearchResult buildSearchResult(SearchResponse response, SearchParam param) {
        SearchResult result = new SearchResult();

        SearchHits hits = response.getHits();
        //1.返回所有查询到的商品
        List<SkuEsModel> esModels = new ArrayList<>();
        if (hits.getHits() != null && hits.getHits().length > 0) {
            for (SearchHit hit : hits.getHits()) {

                String sourceAsString = hit.getSourceAsString();
                SkuEsModel esModel = JSON.parseObject(sourceAsString, SkuEsModel.class);

                if (!StringUtils.isEmpty(param.getKeyword())) {
                    HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                    String highTitle = skuTitle.getFragments()[0].string();
                    esModel.setSkuTitle(highTitle);
                }

                esModels.add(esModel);
            }
        }
        result.setProducts(esModels);

        //2.当前所有商品涉及到的属性信息
        List<SearchResult.AttrVo> attrVos = new ArrayList<>();
        ParsedNested attr_agg = response.getAggregations().get("attr_agg");
        ParsedLongTerms attr_id_agg = attr_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();
            //1.得到属性的id
            long attrId = bucket.getKeyAsNumber().longValue();
            //2.得到属性的名字
            ParsedStringTerms attr_name_agg = bucket.getAggregations().get("attr_name_agg");
            String attrName = attr_name_agg.getBuckets().get(0).getKeyAsString();

            //3.得到属性的所有值
            ParsedStringTerms attr_value_agg = bucket.getAggregations().get("attr_value_agg");
            List<String> attrValues = attr_value_agg.getBuckets().stream().map(item -> {
                String keyAsString = item.getKeyAsString();
                return keyAsString;
            }).collect(Collectors.toList());

            attrVo.setAttrId(attrId);
            attrVo.setAttrName(attrName);
            attrVo.setAttrValues(attrValues);

            attrVos.add(attrVo);
        }
        result.setAttrs(attrVos);

        //3.当前所有商品涉及到的品牌信息
        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        ParsedLongTerms brand_agg = response.getAggregations().get("brand_agg");
        for (Terms.Bucket bucket : brand_agg.getBuckets()) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();
            //1.得到品牌的id
            long brandId = bucket.getKeyAsNumber().longValue();
            //2.得到品牌的名字
            ParsedStringTerms brand_name_agg = bucket.getAggregations().get("brand_name_agg");
            String brandName = brand_name_agg.getBuckets().get(0).getKeyAsString();
            //3.得到品牌的图片
            ParsedStringTerms brand_img_agg = bucket.getAggregations().get("brand_img_agg");
            String brandImg = brand_img_agg.getBuckets().get(0).getKeyAsString();

            brandVo.setBrandId(brandId);
            brandVo.setBrandName(brandName);
            brandVo.setBrandImg(brandImg);

            //TODO 名字与图片从数据库再查一次,刷新数据,因为品牌保存的时候,并没有同步修改索引库
            //TODO 或者修改品牌的时候，修改索引库
            /*
            R r = productFeignService.brandInfo(brandId);
            if (r.getCode() == 0) {
                BrandBo brandBo = r.getDataByKey("brand", new TypeReference<BrandBo>(){});
                brandVo.setBrandName(brandBo.getName());
                brandVo.setBrandImg(brandBo.getLogo());
            }
            */

            brandVos.add(brandVo);
        }
        result.setBrands(brandVos);


        //4.当前所有商品涉及到的分类信息
        ParsedLongTerms catalog_agg = response.getAggregations().get("catalog_agg");
        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        List<? extends Terms.Bucket> buckets = catalog_agg.getBuckets();
        for (Terms.Bucket bucket : buckets) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            //得到分类id
            String keyAsString = bucket.getKeyAsString();
            catalogVo.setCatalogId(Long.parseLong(keyAsString));

            //得到分类名
            ParsedStringTerms catalog_name_agg = bucket.getAggregations().get("catalog_name_agg");
            String catalog_name = catalog_name_agg.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catalog_name);

            catalogVos.add(catalogVo);
        }
        result.setCatalogs(catalogVos);

        //5.分页信息-当前页码
        result.setPageNum(param.getPageNum());
        //5.分页信息-总记录数
        long total = hits.getTotalHits().value;
        result.setTotal(total);
        //5.分页信息-总页码
        int totalPages = (int) total % ESConstant.PRODUCT_PAGESIZE == 0 ? (int) total / ESConstant.PRODUCT_PAGESIZE : ((int) total / ESConstant.PRODUCT_PAGESIZE + 1);
        result.setTotalPages(totalPages);
        //5.分页信息-所有可用的页码
        List<Integer> pageNavs = new ArrayList<>();
        for (int i = 1; i <= totalPages; i++) {
            pageNavs.add(i);
        }
        result.setPageNavs(pageNavs);

        //6.属性的面包屑导航
        if (!CollectionUtils.isEmpty(param.getAttrs())) {
            List<SearchResult.NavVo> navs = param.getAttrs().stream().map(attr -> {
                //1.分析attrs传递的查询条件
                SearchResult.NavVo navVo = new SearchResult.NavVo();
                String[] s = attr.split("_");
                navVo.setNavValue(s[1]);
                R r = productFeignService.attrInfo(Long.parseLong(s[0]));
                //当前传递过来的所有属性
                result.getAttrIds().add(Long.parseLong(s[0]));
                if (r.getCode() == 0) {
                    AttrResponseVo attrResponseVo = r.getDataByKey("attr", new TypeReference<AttrResponseVo>() {});
                    String attrName = attrResponseVo.getAttrName();
                    navVo.setNavName(attrName);
                } else {
                    navVo.setNavName(s[0]);
                }

                //2.取消了这个面包屑以后,我们要跳转到哪个地方,将请求地址的url里条件置空
                //拿到所有的查询条件,去掉当前 attr=1_以官网信息为准
                String replace = this.replaceQueryString(param, attr, "attrs");
                navVo.setLink("http://search.shopifymall.cn/list.html?" + replace);

                return navVo;
            }).collect(Collectors.toList());

            result.setNavs(navs);
        }

        //7.品牌的面包屑导航
        if (!CollectionUtils.isEmpty(param.getBrandId())) {
            List<SearchResult.NavVo> navs = result.getNavs();
            SearchResult.NavVo navVo = new SearchResult.NavVo();

            R r = productFeignService.brandsInfo(param.getBrandId());
            if (r.getCode() == 0) {
                List<BrandBo> brands = r.getDataByKey("brands", new TypeReference<List<BrandBo>>(){});
                StringBuffer buffer = new StringBuffer();
                String replace = "";
                for (BrandBo brandBo : brands) {
                    buffer.append(brandBo.getName() + ";");
                    replace = this.replaceQueryString(param, brandBo.getBrandId().toString(), "brandId");
                }
                navVo.setNavName("品牌");
                navVo.setNavValue(buffer.toString());
                navVo.setLink("http://search.shopifymall.cn/list.html?" + replace);
            }

            navs.add(navVo);
        }

        //8.分类的面包屑导航 TODO,不需要导航取消,不需要link

        return result;
    }


    /**
     * 特殊符号替换
     * @param param
     * @param value
     * @param key
     * @return
     */
    private String replaceQueryString(SearchParam param, String value, String key) {
        String encode = null;
        try {
            encode = URLEncoder.encode(value, "UTF-8");
            encode = encode.replace("+", "%20");//浏览器对空格编码和java不一样
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        String replace = param.get_queryString().replace(key + "=" + encode, "");
        return replace;
    }
}
